Energy efficiency in electronics—particularly those that depend on a finite source for operational power—is an important concern to device engineers and is often a significant limiting factor in the work of product designers. With battery-powered mobile devices becoming ubiquitous in both business and personal settings, the problem of improving energy efficiency remains as important as ever. Accordingly, research and development efforts to enhance energy efficiency in such devices are numerous and varied, ranging from improvements in hardware materials and architecture to operating system scheduling efficiency and improved device resource management at the application level.
Existing systems typically rely on a single power source (e.g. a single battery) from which to draw needed power, regardless of the status of the device's hardware and software functions. Even in the increasingly common systems which use multiple battery cells, the component cells or other divisions of the battery pack are typically treated by the device as a single battery module.
Under the present common single-entity power source paradigm, all power loads from the device are served by the single power source regardless of the type of load (e.g. a background application or process versus a streaming video). Even in systems having multiple, individually accessible battery modules, loads are typically assigned to the batteries in a manner that does not take into account the inherent and varying properties of the batteries. For example, it is typical for all loads to be assigned to a single battery until that battery's energy is exhausted, at which point all loads are assigned to another battery until that one is exhausted, and so on. Other typical systems continuously divide loads up as equally as possible between battery modules such that the state of charge of all batteries available to a system remains substantially uniform, or “balanced”.
Systems commonly represented in the art make it difficult or impossible to take into account the varying percentages of wasted energy, which depend in part on the properties of the load and state of the battery, or to take advantage of those known properties when designing a device or system.